Trigger device



E. T. WILBU R TRIGGER DEVICE July 11, 1950 4 Sheets-Sheet 1 Filed Feb.8, 1945 CONDENS ERS INVENTOR. EVER ETT 'IZWILBUR [Mi/U44 A9 #111ATTORNEY July 11, 1950 E. T. WILBUR 2,514,433

TRIGGER DEVICE Filed Feb. 8, 1945 4 Sheets-Sheet 2 TRIGGERED CIRCUITFIG.iO

TRIGGERED CIRCUIT INVENTOR. EVERETT T.-WILBUR BY 1.9. e,

ATTORNEY E. T. WILBUR TRIGGER DEVICE July 11, 1950 4 Sheets-Sheet 3Flled Feb. 8, 1945 I A I I I I I I I I 360 Fl (3 6 AT TORNEY July 11,1950 E. T. WILBUR 2,514,433

TRIGGER DEVICE Filed Feb. 8, 1945 4 Sheets-Sheet 4 FIG.8 FIG.9

CIRCUIT TO BE TFUGGERED INX'IFNTUK EVERETT T4 WK LB U R ATTORNEYPatented July 11, 1950 UNITED STATES PATENT OFFICE (Granted under theact amended April 30, 1928; 370 0. G. 757) 4 Claims.

The invention described herein may be manufactured and used by or forthe Government for governmental purposes, without the payment to me ofany royalty thereon.

This invention relates to a triggering device for controlling theangular or temporal relationship of impulses within a cyclical series.

The objects of the present invention comprise the provision of animproved type of triggering device that simultaneously varies the phaserelationship of a cyclical series with that of an electrical,mechanical, or other device with which it may be coupled; provides adevice wherein the variation in phase relationship may operate tocompensate for imperfections in other components in a system of which itforms a part; and provides a device which may be adjusted during thetime its associated equipment is in continuous operation.

With the above and other objects in view that will be apparent to thosewho are informed in the field of triggering devices from the followingdescription, suitable embodiments of the present invention are shown inthe accompanying drawings, wherein:

Fig. 1 is an elevational and block diagram view of an assembly thatembodies the present invention;

Fig. 2 is an elevational view taken from the line 22 in Fig. 1 lookingin the direction that is indicated by the arrows;

Fig. 2a is a simplified tabulation, explanatory of changes in operatingeffects of my improved device, brought about by adjustment of certainparts thereof;

Fig. 3 is an elevational view taken from the line 3-3 in Fig. '1 lookingin the direction that is indicated by the arrows;

Fig. 4 is a perspective view of a calibrated adjustable componentsupporting part of the device that is shown in Fig. 1;

Fig. 5 is a diagram of pulse signals that are emitted by the presentdevice over its full range in sequence efiected by radial displacementonly of the photoelectric tube;

Fig. 6 is a diagram of pulse signals from the .device in sequenceefiected by tangential displacement only of the photoelectric tube;

Fig. 7 is a fragmentary elevational view of a mechanical modification ofthe device that is shown in Figs. 1, 2 and 3.

of March 3, 1883, as

Fig. 8 is an enlarged section taken along the line 8--8 of Fig. 7;

Fig. 9 is an elevational view of another modification in the device thatis shown in Figs 1, 2 and 3;

Fig. 10 is an enlarged section taken along the line l0l0 of Fig. 9; and

Fig. 11 is an illustrative schematic circuit for being interposedbetween the device that is contemplated hereby and a circuit to betriggered.

The first form of triggering device that is illustrated in theaccompanying drawings comprises an opaque disc I that is apertured inany desired number of narrow slots 2, 2', etc., that extend in angularrelation. with respect to radii of the disc I. The slots 2, 2, etc. aresufiiciently inclined with respect to the radii of the disc I so thatthe dash line outer are a is less than the are E), the inner arc c isless than the are d, and the intermediate are e is equal to the are 1.This relation of arc-lengths is tabu-= lated in Fig. 2a. The disc l ispower driven in any desired manner, as by a motor 3, and is mountedbetween supporting blocks 4 and 5 upon the shaft 6 thereof. A lightsource l0 continuously emits light rays that energize a light-sensitiveelement in a photoelectric tube It thru the slot 2, or 2', of the disc iwhen a slot is interposed between the light source Hi and the tube llduring the rotation of the disc I The unslotted portions of the opaquedisc I interrupt light rays that are, directed toward the photoelectrictube from the light source l0 and prevent the triggering of the tube H.

The light source [0 preferably is adjustably mounted for both radial andtangential movement with respect to the disc i in any desired manner, asby operation of an adjustable component supporting device that is showntherebelow and also in Fig. 4 of the drawings. The light source l0preferably is mounted upon a stem part 23 of a slide part I2 of thecomponent supporting device, and is moved tangentially of the disc I byoperation of a screw l3. The slide 42 is movably dovetailed upon anotherslide Hi that carries a flange l5 thru which the screw l3 threads, asshown in perspective in Fig. 4 of the drawings. The slide I4 isadjustable radially of the disc I by operation of a screw 16. The screwl6 threads thru a flange part ll of a rigidly mounted base plate I8 withwhich the slide I4 is dovetailed. In this atlases 3 manner the positionof the light source is is adjustable tangentially of the disc l byoperation of the screw I3 and radially of the disc 6 by operation of thescrew I6. The adjustable support that is so provided preferably iscalibrated for linear movement as shown in Fig. 4 and permits theaccurate adjustment of the light source it with respect to the inclinedslots 2 and 2' in the rotatable disc i, where a pin point light sourceis preferred. Where the light source it is not shielded, it may bepermanently mounted in any suitable manner.

The photoelectric tube ii in a similar manner is adjustably mounted fora desired alignment with respect to the inclined slots 2 and 2' in thedisc i. A preferred mounting for the photoelec= tric tube ii issubstantially an inverted duplication of the mounting for the lightsource iii. The photoelectric tube ii is mounted upon a stem part 29 ofa slide 2&3 that is moved tangentially of the disc 1. by a screw 28. Thescrew 2i threads thru a flange portion 22 of another slide 23 with whichthe slide 20 is dovetailed, and that in turn is movably dovetailed to abase plate 25. The slide 23 is moved radially of the disc 9 by operationof a screw 25. The screw 25 threads thru a flange portion it of the baseplate 2Q. Screws it serve to secure firmly the base plates l8 and 253 toany suitable rigid supports 8t and Si, respectively.

The motor 3 preferably also serves to continuously variably tune thepanoramic sweep of a radio receiver circuit by continuously rotating aplurality of variable condenser plates 32, that are mounted upon themotor shaft 5, thru a plurality of fixed condenser plates 33 thatcomprise a splitstator tuning condenser or the like. The continuouslyvariable capacitor, comprising the moving plates 32 and the fixed plates33, provides a continuous sweep for the tuning of a panoramic receiver,or the like.

Control pulse sequences eflected by the adjustment of the photoelectrictube ll radially only of the disc 5, are represented in Fig. 5 oi theaccompanying drawings.

Control pulse sequences effected by the adjustment of the photoelectrictube ll tangentially only of the disc I, are represented in Fi 6 of theaccompanying drawings.

The normal pulse sequence, when the photoelectric tube H is disposedsubstantially at the arcs e and j that are midway between the radialinner and outer ends of the slots 2, 2' etc., in the disc I, and wherethe arcs e and f are of equal length, is represented in the pulsesequence K of Fig. 5. As shown in the pulse presentation K, the pulsesare equidistant from each other, i. e., are spaced equally from eachother in point of time.

The pulse sequence when the photoelectric tube II is disposed at theradially outer ends of the slots 2, 2' etc., in the disc 5, or on thearcs a. and b, is represented as the pulse sequence L in Fig. 5. In thispulse sequence L, since the arc a. is of shorter length than the arc b,and since the rate of rotation of the disc I is uniform in point oftime, the arc a, with the photoelectric tube it as reference point, istraversed in a shorter elapsed time interval than is the arc b. Inharmony with this concept, the time and distance a on the pulse sequencepresentation L is shorter than the time and distance I), and also isshorter than the linear arc. time and distance e, or its equal, thelinear are time and distance 1. Since the disc I rotates continuously ata uniform rate ill) thru a full turn, or thru 360, the difference inelapsed time between the travel time over the arc a and the travel timeover the are I, or its equal the are e, is equal to, but is of oppositesign to. the dlfl'erence in elapsed time between the travel time overthe are I: and the travel time over the are e, or on a time basis:

The pulse sequence when the photoelectric tube H is disposed at theradially inner ends of the slots 2, 2', etc., in the disc 9, or on thearcs c and d, is represented as the pulse sequence M in Fig. 5. In thispulse sequence and on a time basis, in a similar manner:

since the arm c is traversed in a shorter period of time than is the aree and the are d is traversed in a greater period of time than is the arei, where the photoelectric tube it is moved radially only of the disc 5.

It will thus be noted that the radial movement only of thephotoelectrlcal tube 5 i, as represented by the vertical line B in Fig.2c, adjusts the time duration between adjacent pulses in alternate 180arcs. When th time duration is adjusted at one extreme, the arc may bemade appreciably less than 180, and at the other extreme the same aremay be made appreciably greater than 180. An increase in one are isaccompanied by a decrease in the diametrically opposite arc.

The pulse sequence when the photoelectrical tube H is moved tangentiallyonly of the disc 8, as represented by the horizontal line T in Fig. 2c,is shown in Fig. 6. In this presentation the radial distance between thecenter of the disc l and the tube H remains substantially constant fortangential changes in position of the tube H. In this presentation,tangential movements only of the tube ll shifts the phase of the pulsesequence series.

The pulse sequence, when the photoelectric tube H is disposed at theradius of the are e or f. and is moved tangentally toward thepulse-delaying or radially-outer end of the slots 2, 2, etc., is delayedin point of time, as represented in the pulse sequence presentation 0,as compared with the normal reference presentation N in Fig. 6. Thereference presentation N in Fig. 6 is the same as the referencepresentation K in Fig. 5.

The pulse sequence, when the photoelectric tube ii is moved tangentiallyfrom the midline of the slot 2 or 2 toward the earlier or radiallylnnerend of one of the slots, is represented in the pulse sequencepresentation P in Fig. 6. In this presentation P, the pulse sequence isearly in point of time as compared with the reference presentation N. Ingeneral, the tangential movement only of the photoelectric tube H shiftsthe phase of the series with respect to a fixed point upon the disc i.

The present device serves to efiectually compensate for electricalirregularities that arise out of physical imperfections in split-statortuning condensers, the presence of electrical fields about amuse mltsaccuracy in aligning the number of electrical degrees that are traversedby diametricallyopposed condenser plates on a split-stator tuningcondenser that may arise from mechanical imperfection in the condenserplates and the proximate mounting thereof, or from the inductive efiectof electrical apparatus within the electrical field of which the tuningcondenser plates are caused to operate. The device may be used in anyapplication wherein it is necessary to compensate for or to determinethe degree of discrepancy between successive 180 pulses, or otherrelated recurrent phenomena.

The degree of divergence of each pulse from a true 180 for a givenradial adjustment can be controlled by the angle 01' the slot withrespect to the radius of the disc I. The thinner the slots 2, 2', etc.,are made, the more accurate the device In operation, the photoelectrictube H is adjusted tangentially and radially with respect to v the slots2 and 2' in the disc I, by operation of the screws 2| and 25,respectively. This adjust ment permits advantage to be taken of thetriggering variation upon opposite sides oi the dash line arcs e and fon the disc I. The arcs e and f are of equal length and providetriggering at equal time intervals and in uniform electrical sequence,as indicated in the signal presentation K of Fig. 5 of the drawings.When the photoelectric tube H is moved radially outwardly of the disc i,the electrical sequence along the are a is shortened and the sequencealong the arc b is lengthened, as indicated in the sequence L of Fig. 5.When the photoelectric tube H is moved radially inwardly of the disc theelectrical sequence is lengthened along the are d and is shortened alongthe arc c as indicated in the sequence M of Fig. 5.

The adjustment of the photoelectric tube H, with respect to the slots 2,2 etc., in the opaque disc i, allows for corrections in a device whichmust be triggered precisely at every electrical 180. In a situationwhere it is necessary to compensate for variations in electricalsequence in alternate 180 arcs by the adjustment of the device, anytendency for one are to be longer than the other can be corrected by theradial adjustment of the photoelectric tube ii.

In the event that it is necessary to shift the whole series ofelectrical sequence, this result can be achieved by the tangentialadjustment of the photoelectrical tube H. By means of both the radialand tangential adjustment of the photoelectrical tube H with respect tothe slots 2, 2' etc., in the disc l, a wide variety of combinations ofpulse arrangements can be accomplished.

A mechanical modification of the same invention is shown in l of theaccompanying drawings. In this construction, a non-conducting disc 35 ismounted rotatably in a plane that is normal to the motor shaft 5. Thedisc 35 is disposed at the end of shaft 5, and beyond the condensers 32,33, and between plates 36 and 31 that are secured by a nut 38 thatthreads on the end of the motor shaft 6, or the like.

The disc 35 carries one or more conducting strips 40 that are inclinedwith respect to the radii of the disc 35, in a manner that is similar tothe disposition of the slots 2, 2', etc., in the disc ii. Each of theconducting strips 40 engages in wiping contact with each rotation of thedisc 35 by wiping brushes on the ends of a pair of spring metalcontactarms 4| and 42. The con tact arms 4| and 42 are supported by anon-conducting stem 43 that extends upwardly from the top tangentialslide 44 of a contact-supporting and adjusting table. The tangentialslide 44 is slidably dovetailed to a radial slide 45 which, in turn, isslidably dovetailed to a base plate that is firmly supported as in thepreviously described constructions. The adjustment of the moveableslides 44 and 45 of the table is controlled by a tangential screw 46 anda radial screw 41 as in the device that is shown in Fig. 4. The contactarms 4| and 42 are in electrical connection with the circuit 48 that isto be triggered. The pair of contacts 4| and 42 are adjustable radiallyof the disc 35 by operation of the screw 41, and tangentially of thedisc 35 by operation of the screw 46, so that the brush ends of the pairof contacts 4| and 42 may be moved along substantially the full lengthof the contact strip 40. The electrical sequence of the contact isshortened along the are a when the brush contact ends of the pair ofarms 4| and 42 are moved radially outwardly of the disc 35, andlengthened along the arc b when the contacts are moved radially inwardlyof the disc. The disc 35 is non-conducting, and hence circuit betweenthe arms 4| and 42 is only completed when the brush ends thereof are insimultaneous electrical contact with one of the conducting strips 49.

A further modification in the present invention is shown in Figs. 9 and10 of the accompanying drawings. In this construction, a disc 50 ofnon-magnetic material has embedded therein a desired plurality ofmagnetically-conducting armature strips 5|, 5|, etc., that are flushwith-the opposite surfaces of the disc 58 and that are disposed inangular relation with respect to the radii thereof. The disc 50 ismounted upon the motor shaft 5 as is the disc 35, or otherwise asdesired.

' A U-shaped magnet 52 is adiustably mounted with respect to the disc 50in any desired manner, and preferably upon a non-conducting stem part 53of a table slide 54 that is adjustable tangentially of the disc 50 by ascrew 55, and radially by a screw 56 so that the spaced free ends of themagnet 52 may he adjustably moved the full length of the armature strips5|, 5| etc., in the disc 5|). The legs of the magnet 52 carry a desirednumber of turns of a continuous wire 5'7 that terminates in the circuit58 to be triggered.

In operation, as the disc 50 is rotated by the motor 3, the armatures 5iand 5| pass between the spaced poles of the U-shaped magnet 52 and senda triggering electrical impulse thru the wire 51 to the triggeredcircuit 58.

An illustrative circuit between the triggering device shown in Figs. 7and 8, and the circuit to be triggered, is shown in Fig. 11 of theaccompanying drawings. in this circuit the brushes 4| and 42 arepositioned to contact substantially simultaneously the conducting strips40 on the non-conducting disc 35. One of the contacts Si is grounded andthe other contact 42 is supplied current of a desired sign, such as +13as shown, thru a pair of resistors 60 and Bi and is connected thru acondenser 62 to the grid of a triode 53. The junction of the resistors60 and iii is grounded thru a condenser 54. The grid of the tube 53 isgrounded thru a resistor 65. The cathode of the tube 63 is by-passed toground thru a resistor 56 that is shunted by a condenser 51. The plateof the triode 53 supplies amplified triggering signal to the circuit 48.

It is to be understood that the devices and the parts thereof that aredisclosed and described herein and the accompanying circuit therefor,have been submitted for the purposes of illustrating and describingsuitable, operating embodiments of the present invention and thatsimilarly functioning modifications and substitutions therein may bemade without departing from the present invention as defined by theappended claims.

What I claim is:

1. An apparatus for generating a series oi spaced electrical pulsescomprising a member supported for rotation about a fixed axis, meansassociated with said member and responsive to the rotation thereof togenerate said pulses, and means supporting said first-named means andoperable to effect adjustment of the latter with respect to said memberin a direction radially of said axis to adjust the time duration betweenadjacent pulses and in a direction tangentially of certain arcsprescribed by said member during rotation of the same to shift the phaseof said series with respect to a fixed point upon said member.

2. In a trigger device of the character described, means for generatinga series of spaced electrical pulses, a substantially opaque discforming part of said means and supported for rotation about a fixedaxis, said disc being provided with relatively narrow slots disposedrespectively on opposite sides of said axis and inclined with respect tothe radii of said disc, a light source and a light-sensitive elementdisposed respectively on opposite sides of said disc, and meanssupporting said light source and said light-sensitive element andoperable to efiect adjustment of the'same with respect to said disc in adirection radially of said axis to adjust the time duration betweenadjacent pulses and in a direction tangentially of certain arcsprescribed by said disc during rotation of the same to shift the phaseof said serie with respect to a fixed point upon said disc.

3. In a trigger device of the character described, means for generatinga series of spaced electrical pulses, a disc forming part of said meansand supported for rotation about a fixed axis, said disc being ofelectrically non-conducting material and provided with conducting stripsdisposed respectively on opposite sides of said axis and inclined withrespect to the radii of said disc. a pair of metallic contact elements,and means supporting said contact elements for wiping contact with saidstrips with each rotation of said disc to generate said pulses, saidsupporting means being operable to effect adjustment of said contactelements with respect to said disc in a direction radially of said axisto adjust the time duration between adjacent pulses and in a directiontangentially of certain arcs prescribed by said discs during rotation ofthe same to shift the phase of said series with respect to a fixed pointupon said disc.

4. In a trigger device of the character described, means for generatinga series of spaced electrical pulses, a disc of non-magnetic materialforming part of said means and supported for rotation about a fixedaxis, said disc being provided with magnetically-conducting armaturestrips embedded therein and substantially flush with the oppositesurfaces thereof, said strips being disposed respectively on oppositesides of said axis and inclined with respect to the radii of said disc,a U- shaped magnet associated with and embracing said disc forcooperative operating action with said strips to generate said pulses,and means supporting said magnet and operable to eifect adjustment ofthe latter with respect to said disc in a direction radially of saiddisc to adjust the time duration between adjacent pulses and in adirection tangentially of certain arcs prescribed by said disc duringrotation of the same to shift the phase of said series with respect to afixed point upon said disc.

EVERETT T. WILBUR.

REFERENCES CITED UNITED STATES PATENTS Name Date Sawyer Feb. 8, 1881Number

